Casing spear



E. D. POWER CASING SPEAR Sept. 10', 1929.

Filed Oct. 2l. 1926 2 Sheets-Sheet 2 |NVENTOR Eon/A20 -D' POWER'Patented sept. 1o, 1929.

UNITED STATES PATENT OFFICE.

EDWARD D. POWER, OF TAFT, CALIFORNIA, ASSIGNOR OF TWO-EIGHTHS TO LEWIS IE. STEPHENS, F FELLOWS, CALIFORNIA, AND THREE-EIGHTHS T0 ELMORE D.

JONES, OF TAFT, CALIFORNIA.

CASING SPEAR.

Application filed October 21, 1926. Serial No. 143,230.

My invention relates to, and has for a purpose the provision of a casingspear, which is capable of being operated from the top ot' a well togrip a casing at any point within its length in the hole and in suchmanner that the casing can be pulled from the hole, or the sectionsthereof unscrewed or screwed together, the spear being so constructedthat it can be released and reset as many times as desired withoutremoving 4 the spear from the hole for resetting, as has been necessaryin devices of this character heretofore proposed.

A further purpose of my invention is the provision of a casing spearwhich is par* ticularly adapted, although not necessarily ior luse inwells employing the rotary method of drilling, the spear being appliedto the .drill pipe and having gripping elements 2o normally inactive butcapable of being rendered active to move into engagement with the casingupon the pumping of mud fluid into the drill pipe, so that uponelevation of the pipe the casing will be gripped internally and anupward pull exerted on the latter.

lf will describe only one form of casing .spear embodying my inventionand will then point out the novel features thereof in claims.

In the accompanying drawings,

Figure 1 is a view showing in longitudinal vertical section one form ofcasing spear embodying my invention, and inserted into a well casingwith the gripping elements in normal or inactive position,`

Figure 2 is a view similar to Figure 1 and showing the gripping elementsin active position `in gripping relation to the casing,

Figures 3 and 4 are horizontal sectional views taken on the lines 3 3and 4 4 of Figures 1 and 2 respectively, and

Figure 5 is a horizontal sectional view taken on the lines 5 5 of Figure1.

Referring specifically to the drawings, in which similar referencecharacters designate similar parts in each of the several views, myinvention in its present embodiment comprises a body of elongated formdesignated generally at B and havin@r a relatively large bore at itsupper end:` to

lprovide a chamber 10 communicating at its lower end with a centralpassage 11 extending longitudinally through the body. The body isthreaded internally at its upper end to receive the end of a drill pipeP by means of which the body can be lowered into a well casing W tothepoint at which it is desired to grip the casing. The body is reduced indiameter as shown at 12 and is formed with a series of concentric cams13 of frust'ro-conical form arranged in end to end relation with thelarger end of the cams downmost and confronting the smaller end of theadjacent cam.

Gripping elements designated generally at G in the present instance ofelongated form and arcuate cross-section are `arranged in surroundingrelation to the cams 13 and are maintained in definite spaced relationby means of guide ribs 14 extending lengthwise of the body atcircumferentially spaced intervals. It will be noted that four grippingelements have been illustrated but it will be understood that a greateror less number can be used depending on the size of the device.' Thegripping elements are formed on their inner eripheral portions with aseries of cam sur 'aces 15 corresponding in contour and number with thecams 13 while their outer peripheral portions are formed with amultiplicity of transversely extending teeth 16.

The gripping elements are normally urged upwardly on the body B by meansof a coil spring 17 interposed between a collar 18 slidably mounted' onthe reduced extension 19 of the body and a second collar 20 threaded onthe lower end of the extension and locked against movement by means of anut 21 which in turn is positively maintained in definite position by aheaded pin 22, extending through registering openings in the extension19 and nut 21. The lower ends of the gripping elements are looselyreceived in a pocket 23 formed in the collar 18 and engage the conical'bottom 24 of the pocket. The upper ends` of the elements are beveled toprovide cam` surfaces 25 and are re'ceived in the correspondinglytapered bore 26 of a sleeve 27 threaded'l on the body, the cam surfaces25- and bore 26 cooperating to move the upper ends of the elementsinwardly to the inactive or contracted position shown in Figure 1 asthey are urged upwardly by the spring 17. By virtue of the conicalbottom 24 the lower ends of the elements are simultaneio ously urgedinwardly so that the elements will snugly engage the cams 13 to permitinsertion into the casing W.

The elements are adapted to gravitate to the j active or expandedposition shown in .i5 Figure 2 in engagement with the inner wall of thecasing upon the pumping of mud fluid into the drill pipe P. To this enda piston K is mounted in the Chamber and is provided with a packingsleeve 28 adapted to be compressed'by a nut 29 intofluid seal-` ingengagement with the wall of the chamber. Projecting from the lower endof the piston is a rod 30 extending into the passage 11 with its lowerend engaging a rectangularshaped key 31 extending transversely of thebody through diametrically opposed slots 32 formed in the extension 19.The ends of the key project into diametrically opposed openings in thecollar 18 and the key isl maintained against longitudinal displacementby means of pins 33 extending through the key into grooves 34 formed inthe collar. It will thus be clear that any movement of the pistondownwardly will cause a corre- 35 sponding downward movement to betransmitted to the collar 18 through the medium rof the rod 3() and key31 to thus compress the spring 17 and leave the gripping elements freeto gravitate and be simultaneously moved outwardly to the expandedposition shown in Figure 2 by the cams'13. As clearly shown in thisligure. the downward movement of the collar 18 is limited by theabutting of tubular extensions 35 and 36 5 formed on the confrontingsides of the collars 18 and 2() respectively.

To permit free circulation of the mud fluid through the body duringlowering or raising of the gripping device into or out of the hole,l thelpiston K is provided with a valve 37 havinga depending stem 38 andnormally urged upwardly to the open position shown in Figure 1 by a coilspring 39 received in a pocket 40 formed in the piston,

which pocket communicates through ports 41 withthe chamber 10 below thepiston. It will thus be seen that the fluid will be free to circulatethrough the piston K, chamber l() and thence through the passage 11intothe casing. Other ports 42 are formed lin the body to provideadditional vents, while ducts 43 lead from the lower end of the chamber10 to the interior of the sleeve 27 and ports '44 extend through thebody B adjacent the lower endsof the gripping relatively large grippingsurface of the eleelements to permit fluid to work between the elementsand cams 13 and thus flush out any accumulation of sand or other foreignsubstance. J

The operation of the device is as follows:l The device is secured to thedrill pipe P and lowered into the casing W to the point at which it isdesired to grip the latter, the'4 gripping elements, piston, and valve37 Occupyng the positions shown in Figure 1, which is termed in the artthe set position of the spear. 'l'.he valve springs 39 is of suihcientstrength to maintain the valve 37 in its open position against-thenormal cir` culation pressure of the mud fluid so as to 8,0

lpermit the Huid to be circulated in the same manner as when employed indrilling operations. lVhen desiring to release the spear the pressure ofthe liuid is increased, thus overcomingothe tension of the spring 39vandclosing the valve. The fluid now-acts upon and moves the piston K-downwardly, and through the medium of the rod 30 and key 31 t-he'c'ollan18 is moved correspondingly downward to thereby compress the spring 17,thus permitting the gripping elements Grl to gravitate and expand intoengagement with the casing W as is clearly shown in Figure 2. Withv thespear released the drill pipe P is now elevated by the usual elevatingmechanism (not shown) thus causing the.cams 13 to further expand thegripping elements until the teeth 16 thereof have biting engagement withthe casing to thus grip and exert an upward pull upon `the latter. Thepressure upon the fluid may now be out olf as the upward pull upon thecasing is sufficient to maintain the gripping elements in grippingengagement with the casing. By continuing the upward pull y upon thecasing and rotating the drill pipe in .one direction or the other by theusual mechanism (not shown) casing sections may be .screwed together orunscrewd as desired. It will be noted in this coimection l that the ribs14 function to prevent rotation of the elements on the body B duringrotation of the latter by the drill pipe so' th a t the rotativemovement of the bodyv will be` .transmitted through the elements yto thecasing. i

To reset the spear the upward pull on the pipev P is iirst discontinued,then the pipe'is lowered slightly to free the gripping elements from thecams 13 after which the spring 17 ,due to the previous cutting oli ofthepressure on the mud fluid, functions to return the elements and pistonto the posi- `tion shown in Figure 1.

From the foregoing operation it will be 12 clear that the spear can bereleased and reset from the top of the well as often as desired withoutremoving the spear from the hole.` vIt will also be noted that due tothe ments G,the expansion pressure lexerted on the casing is distributedover a large area so that the liability of-burstingfthe casing duringjarring operations is materially lessened.

Although I have herein lshown and de#` scribed only one form ofcasingspear embodying my invention, 1t 1s to be understood that variouschanges and modifications may be made herein without departing from thel spirit of the invention', and thev spirit 'and scope of the appendedclaims.

l claim as my invention:

l. In combination, a drill pipe and a casing spearfsecured' to the pipeand havingr movable gripping elements, means for nor-v mally urging thegripping elements to a collapsed position `for insertion into a wellcasing, and means operable upon the pumping of mud fluid into the pipefor actuating the first means to render the elements free to gravit-ateto an expanded position for engagement with the casing Iin such mannervmeans responsive to the action of mud fluid pumped into the drill pipefor rendering the first means inactive, to thereby permit the elementsto gravitate to an expanded position in engagement with the inner wallof the casing, whereby upon upward movement of the pipe, the elementswill gripand exert an upward pull on the casing.

A casing spear comprising a tubular body adapted to Ibe connectedV to adrill pipe for insertion into a well casing, gripping elements on thebody, co-acting means on the body and elements operable upon movement ofthe latter in one direction to cause the elements to be expanded, asleeve on the body having a cam surface internally thereof and receivingone end portion of said ele-- ments so as tok cause the latter to becollapsed upon movement of said elements vin the other direction, acollar fixed to the body, a second collar slidableon thebody andreceiving the other end portion of said elements, a coil springinterposed between the collars and normally urging said elements tocollapsed position, the .body having a transverse slot,/a key in theslot and operatively connected to the slidable collar, and a piston inthe body having a rod engaging said key for actuating the slidablecollar.

4. A casing spear as embodied in claim 3 wherein said piston is providedwith a valve normally urged to open position, and

ports are provided in the piston and body for the purpose described.

5. A casing spear comprisingl a body adapted to be connected to a drillpipe for insertion into a well casing, gripping elements movablevertically on the body, means operable upon upward movement of ltheelements for causing the latter to move toa collapsed position, meansoperable upon downward movement of the elements for causing the latterto be expanded into engagement with the inner wall of the casing, meansfor normally urging the elements to collapsed position, means responsiveto the action of mud fluid pumped into the drill pipe for rendering thelast means inactive, to thereby permit t'he elements to move to expandedposition, and a valve in the last means normally urged to openpositionso as to permit mud fiuid at a predetermined pressure to passthrough the body, a valve being movable to Closed position under theaction of mud fluid above the predetermined pressureso as to allow thelast4 means to respond to the-action of the fluid.

6. A casing spear comprising a body adapted to be connected to a drillpipe for insertion into a. well. casing, gripping elements movable onthe body, means responsive to liuid pressure in the drill pipe forcontrolling movement of the gripping elements to one` position, andmeans normally operating to allow fluid at a predetermined pressure inthe drill pipe tol discharge from the body without acting on the firstmeans, and operable under the action of the fluid when at a pressure inexcess of the predetermined pressure, to prevent the discharge of thefluid from the body sp that the fluid will act upon the first means.

7. A casing spear comprising a body adapted to be connectedto a. drillpipe for insertion into a wellcasing, gripping elen `ments movable onthe'body, means responsive to fluid pressure in the drill pipe forcontrolling movement of the gripping elements to one position, t-he bodyhaving an outlet, and a valve controlling the outlet, normally urged toan open position to allow fluid at a predetermined .pressure in thedrill .pipe to discharge from the body through said outlet withoutacting on the first means,` the valve being movable to close the outletunder the action of the fluid when at a pressure in excess of thepredetermined pressure so that the fluid will act upon the first means.v

8. A casing spear comprising a body adapted to be connected to a drillpipe for insertion into a well casing, gripping elements movable on thebody, means includinga piston in the body responsive to fluid pressurein the drill pipe for controlling movement of the elements to oneposition, the .piston and body having communicating outlets, and a valvein the piston controlling the outlet therein and normally urged to anopen position to allow fluid at a. predetermined pressure in the drillpipe to dlscharge from the body through said outlets y Withoutaetingupon the piston, the valve.

being movable to close said outlet in the piston, under the action ofthe fluid when at a pressure in excess of the predetermined pressure sothat the fluid will 'act upon the piston.

9. A Casing spear adapted to be secured .to a. drill pipe and havingmovable gripping elements, means normally acting to maintain thegripping elements in a collapsed position for insertion into a Wellcasing, and means operable in response to the pumping of mud iluid intothe drill pipe for rendering the first means ineffective and therebyallow the gripping elements to gravitate to an expanded position forengagement with the Well casing in such man- 1 ner that upon upwardmovement of the pipe the elements Will grip and exert an upward pullupon the pipe.

10. A casing spear adapted to be secured to a drill pipe for insertioninto a Well casing and having movablegripping elements, fluid pressureresponsive'A means for actuating the gripping elements, and means bywhich fluid at a predetermined e pressure will be rendered ineifectivekto act upon the first means, yet incapable 'of preventing fluid at apressure in excess of the predeter- `mined pressure from acting on thefirst means sopthat iluid at the excess pressure Will be free to actupon the first means and actuate the gripping elements.

' EDWARD D. POWER.;

